Sir , if there are 9 LEDs connected in series with the 9 volt battery and each led has a forward voltage drop of 1 volt , do i need a resistor in the circuit (in series with led)?

9 leds each of 1 volt drop is series with 9  volt battery , do we need a resistor?(SMD leds)

I have seen some smd leds without resistor !
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Answer :

We connect resistor to limit the current. So, it depends upon the current rating of the LED, which is provided by manufacturer.
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